As known, an optical disc drive is used to read data from an optical disc or write data into the optical disc. For storing more data, an optical disc with plural data layers has been introduced into the market. For example, a double-sided optical disc comprises two data layers on a top side and a bottom side, respectively.
Generally, the optical disc drive has a single optical pickup head (PUH). For accessing the data of the first side of the double-sided optical disc, the optical disc is loaded into the optical disc drive. When the optical disc is loaded into the optical disc drive, the first side of the optical disc faces the optical pickup head. Consequently, the laser beam emitted by the optical pickup head is focused on the data layer of the first side of the optical disc so as to access the data.
For accessing the data of the second side of the double-sided optical disc, the optical disc is ejected from the optical disc drive. After the optical disc is turned over, the optical disc is loaded into the optical disc drive again, wherein the second side of the optical disc faces the optical pickup head. Consequently, the laser beam emitted by the optical pickup head is focused on the data layer of the second side of the optical disc so as to access the data.